As is well known in the art, the preparation of dentures involves the following steps:
(a) imprints of the gums of a subject are made with agar or suitable material (called the "negative");
(b) a model of each "negative" is made in plaster (called the "positive");
(c) the model is placed in the lower half of a flask and a surrounding parting surface is provided;
(d) the model is covered with a thin layer of wax into which a set of teeth is embedded;
(e) the upper half of the flask is added and filled with plaster, which, when set, holds the teeth in position;
(f) the wax is removed and the denture material is introduced;
(g) the denture material, usually a resin-type plastic, is cured.
Till now the last two steps were done in separate operations. For example, the removal of wax is usually carried out in an ordinary sink under the hot water faucet, thus creating the problem of wax accumulating in the drain and plugging the same when the wax hardens. To overcome this disadvantage, U.S. Pat. No. 3,061,898 to Maliszewski discloses a basin which incorporates a hand-held hose and nozzle. The latter is either directed into the basin containing the flasks to be dewaxed or over the top of the basin where the flasks are held by tongs with the other hand. This can be dangerous as the flasks are usually cleaned of wax by water close to or at the boiling point.
Two other U.S. patents describe a process and apparatus directed to cure the denture material properly: U.S. Pat. Nos. 2,498,368 and 2,360,986 to Harrison and Taub, respectively. However, neither of these patents disclosed a basin wherein both the dewaxing and curing steps can be carried out simultaneously or consecutively; the first Patent being a process and the second Patent being an apparatus adapted to cure a flask by placing a heating element inside the latter.